Boron Incorporation Induces Lattice Expansion in Platinum Nanoparticles for Enhanced Oxygen Reduction Reaction

The oxygen reduction reaction (ORR) is a key cathodic process in zinc‐air batteries, while its sluggish kinetics and the limited stability of Pt nanoparticles constrain practical performance. Achieving high activity, selectivity, and stability while minimizing Pt loading remains a key objective in electrocatalyst design. Herein, B‐doped Pt nanoparticles supported on carbon nanobowls (B‐Pt/CNBs) with an estimated Pt:B:C atomic ratio of 1.00:0.86:98.14 were synthesized by an ice‐bath reduction strategy. In alkaline media, B‐Pt/CNBs deliver an onset potential of 1.073 V versus RHE and a half‐wave potential of 0.966 V versus RHE, with an electron transfer number close to 4 and an H 2 O 2 yield below 5%. The catalyst also shows enhanced methanol tolerance and durability, retaining 92.3% of its initial ECSA after 10 000 CV cycles. DFT free‐energy calculations show that B doping decreases the uphill free‐energy changes for the conversion of O* to OH* and OH* to H 2 O, facilitating the protonation and removal of oxygen‐containing intermediates. This work demonstrates B doping as an effective strategy for designing active and durable low‐Pt ORR electrocatalysts.